synaptic vesicle(redirected from Presynaptic vesicle)
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Related to Presynaptic vesicle: synaptic cleft, synaptic gap
synaptic vesicle[si¦nap·tik ′ves·ə·kəl]
A small membrane-bound structure in the axon terminals of nerve cells that contains neurotransmitters and releases them by exocytosis when an action potential reaches the terminal.